Authentication, e.g., via human voice, may be used to identify a user of a computing device, e.g., for security purposes. Additionally, audio input may be used to communicate commands, data, etc. Due to ease with which to surreptitiously record sounds, issues of recognition and replay attacks may arise when a voice password or a passphrase is reused.
One approach for authentication is to request that the user speak a unique passphrase, e.g., random words, during each identification/authentication session. The uniqueness of the phrase may dissuade attackers from reuse of the recording. However, it may be difficult for the user to pronounce the passphrase, and may be difficult for the computer to determine authenticity without a learning period.